Body Fat Calculator
Estimate your body fat percentage using the US Navy circumference method — one of the most accurate non-invasive formulas. Enter your measurements to see your fat percentage, category and lean mass.
| Category | Men | Women |
|---|---|---|
| Essential fat | 2–5% | 10–13% |
| Athlete | 6–13% | 14–20% |
| Fitness | 14–17% | 21–24% |
| Average | 18–24% | 25–31% |
| Obese | 25%+ | 32%+ |
Please enter valid values.
How to use
- Select your sex and enter your age, weight and height.
- Measure and enter your neck circumference (at the narrowest point) and waist (at the navel for men, narrowest point for women). Women also enter hip circumference.
- Click Calculate to see your body fat percentage, category and lean body mass.
Frequently asked questions
How accurate is the US Navy formula?
The US Navy formula has a margin of error of about ±3–4% compared to DEXA scans. It is more accurate than BMI for estimating body composition but less precise than hydrostatic weighing or DEXA.
Where do I measure my waist?
For men, measure at the navel (belly button). For women, measure at the narrowest point of the torso, usually just above the navel. Stand relaxed and breathe normally — do not suck in.
What is lean body mass?
Lean body mass is everything in your body except fat: muscle, bone, organs, water and connective tissue. It is calculated as: weight × (1 − body fat %).
Is this medical advice?
No. Body fat estimates are screening tools, not medical diagnoses. Consult a healthcare professional before making significant changes to your diet or exercise routine.
Why is essential fat different for men and women?
Women need more essential fat (10–13%) than men (2–5%) to support hormonal functions, pregnancy and other physiological needs. This is normal and healthy.